在南加利福尼亚州的裂区域下面的石质层稀释
Vedran Lekic1, Scott W French, Karen M Fischer
1Department of Geological Sciences, Brown University, Providence, RI 02912, USA. vedran_lekic@brown.edu
概括
构造板块裂变导致大陆和海洋的进化. 这项研究揭示了裂区域的石质层稀薄,表明有效的应变局部化和对称延伸,而不是简单的剪切.
科学领域:
- 地质物理学 地质物理学
- 构造学 构造学 构造学 构造学
- 地球科学 地球科学 地球科学
背景情况:
- 大陆和海洋的进化是由构造板裂变驱动的.
- 了解裂变期间的石质层变形至关重要,但仍然不太了解.
研究的目的:
- 为了研究石灰岩层在裂变过程中的变形过程.
- 为了限制石质层稀薄和应变局部化在裂纹区域.
主要方法:
- 在南加利福尼亚州的裂区和相邻地区下面利用远震剪波散射.
- 解决了石灰岩层-石灰岩层边界和石灰岩层厚度变化.
主要成果:
- 在裂区域下方观察到大量和横向突发的石质层稀释.
- 在索尔顿峡谷确定了有效的菌株局部化,具有显著的地幔石化层稀释或新的石化层创造.
- 没有发现表面和深层岩层变形之间的系统偏移.
结论:
- 结果与对称的石质层延伸相一致.
- 排除了沿着单向的浅潜切割区域的简单切割作为主要的变形机制.
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